What Percentile Is an Average Score? (Mean = Score)
When your score equals the mean, you are exactly at the 50th percentile, outperforming half of all test-takers.
How to use this tool
- Enter your test score.
- Enter the mean (average) score of the reference group.
- Enter the standard deviation of that group's scores.
- Read your z-score and percentile rank.
Confirm that scoring exactly at the mean of any test puts you right at the 50th percentile.
Frequently asked questions
- What does a percentile rank actually mean?
- If your percentile is 90, you scored at or above about 90% of the reference group. It is a relative measure of standing, not the percentage of questions you got right.
- Does this assume a normal distribution?
- Yes. The conversion uses the normal (bell) curve, which fits many large standardized tests well but can misstate percentiles for skewed or small-sample score sets.
- Where do I get the mean and standard deviation?
- From the test's published statistics or your class data. Many standardized tests publish a mean and standard deviation (for example, a mean of 100 with a standard deviation of 15).